Joe Stevens, father of Harry, George, Albert John (‘Jack’), and Joe Stevens Junior, was an engineer who owned the Stevens Screw Company Ltd, in Wednesfield in the English Midlands. Stevens had a reputation for quality engineering before the company built its first motorcycle in 1897, using a Mitchell single-cylinder four-stroke imported from the USA. Before long, Stevens began making engines, starting off with a better-built version of the Mitchell but the family soon developed their own designs, including parallel-twins and V-twins, which were sold as proprietary engines to other manufacturers.

In 1909, after a motorcycle fitted with a Stevens side-valve single-cylinder engine won a trophy for a 24-hour non-stop run in 1909, Jack Stevens decided to contest the Tourist Trophy in the Isle of Man. A new company, A J Stevens & Co (AJS), was founded, with premises in Retreat Street, Wolverhampton,England to manufacture motorcycles and the first model appeared at the Motor Cycle Show in 1910. Albert John Stevens lent his initials to the company, but it remained a family concern.

By 1931 the company was in financial trouble and filed for bankruptcy. After the firm was sold, the name AJS continued to be used within the Associated Motorcycles (AMC) empire. By the 1960s AMC was itself in difficulties. After the AJS name was sold again in 1974 it continued to be used on lightweight, two-stroke scramblers and today on small-capacity roadsters and cruisers.

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